CVE-2021-20866
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5...
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5.11 contain a missing authorization vulnerability in obtaining the user list which may allow a user to obtain the unauthorized information via unspecified vectors.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5.11 contain a missing authorization vulnerability in obtaining the user list which may allow a user to obtain the unauthorized information via unspecified vectors.
- Record
CVE-2021-20866- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 4.0 Medium
AV:N/AC:L/Au:S/C:P/I:N/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
CVE List No score
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5.11 contain a missing authorization vulnerability in obtaining the user list which may allow a user to obtain the unauthorized information via unspecified vectors.
- Record
CVE-2021-20866- Updated
- 2026-11-02
EUVDEUVD-2021-8275 No score
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5.11 contain a missing authorization vulnerability in obtaining the user list which may allow a user to obtain the unauthorized information via unspecified vectors.
- Record
EUVD-2021-8275- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-gcpg-c569-xfr4 No score
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5...
Advanced Custom Fields versions prior to 5.11 and Advanced Custom Fields Pro versions prior to 5.11 contain a missing authorization vulnerability in obtaining the user list which may allow a user to obtain the unauthorized information via unspecified vectors.
- Record
GHSA-gcpg-c569-xfr4- Weakness
- CWE-862
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20866 is a medium vulnerability (CVSS 6.5) in Advancedcustomfields Advanced Custom Fields, published December 13, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.79%, the 78th percentile. No source names a fixed version.